With Stevenson's blessing, we've combined his graphic with the modern Tube map to show where these ghost stations are. The old version is displayed first in the animations below.

Check it out (give it a little time to load, though):

David Stevenson/David Maryk/TfL/Rob Price

Hard to make out the details? Here's the centre of London:

David Stevenson/David Maryk/TfL/Rob Price

In the North West, the Tube once almost reached Bicester and Bletchley. Brill was closed in 1935 due to lack of passengers and subsequently demolished.

David Stevenson/David Maryk/TfL/Rob Price

Further south, it used to service Slough. The line was cancelled in 1885 due to low passenger numbers.

David Stevenson/David Maryk/TfL/Rob Price

Visiting the seaside used to be as simple as hopping on the District line and riding it all the way to Southend or Shoeburyness. The limited service was cancelled with the onset of World War II, and never restarted.

David Stevenson/David Maryk/TfL/Rob Price

But what does a "ghost station" look like in practice? There's some photos of Aldwych floating around online, a discontinued stop near the strand.

Here's Aldwych from the outside (it was originally called Strand Station, and the sign was later hidden but never removed):